/* --- DESIGN SYSTEM & CSS VARIABLES --- */
:root {
  /* System Fonts */
  --font-sans: "Inter", "Outfit", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-serif: "Lora", "Playfair Display", "Georgia", serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;

  /* Editoral Light Theme */
  --bg-primary: #fbfbf9; /* Ivory / Warm off-white */
  --bg-secondary: #f4f4f2;
  --bg-tertiary: #eaeaea;
  --bg-surface: #ffffff;

  --text-primary: #222222; /* Charcoal */
  --text-secondary: #555555;
  --text-tertiary: #888888;

  --accent: #7a1b1b; /* Dark red / Bordo */
  --accent-light: #f7e6e6;
  --accent-dark: #4f1111;

  --gradient-primary: transparent;
  --gradient-secondary: #fbfbf9;
  --gradient-hero: #fbfbf9;
  --gradient-glass: transparent;

  --glass-bg: transparent;
  --glass-border: transparent;
  --glass-shadow: none;

  --success: #2e6644;
  --success-light: #e6f4ea;
  --warning: #805b10;
  --warning-light: #fef7e0;
  --danger: #7a1b1b;
  --danger-light: #f7e6e6;

  /* Borders & Dividers */
  --border-color: #dddddd;
  --border-focus: #7a1b1b;

  /* Shadow Elevation */
  --shadow-sm: none;
  --shadow-md: none;
  --shadow-lg: none;
  --shadow-xl: none;

  /* Layout Constants */
  --radius-sm: 2px;
  --radius-md: 4px;
  --radius-lg: 8px;
  --radius-round: 50%;
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --container-width: 1040px;
  --container-narrow: 720px;
}

/* --- DARK MODE SELECTORS --- */
[data-theme="dark"] {
  --bg-primary: #0a0a09;
  --bg-secondary: #121211;
  --bg-tertiary: #1c1c1b;
  --bg-surface: #10100f;

  --text-primary: #eaeaea;
  --text-secondary: #a0a0a0;
  --text-tertiary: #666666;

  --accent: #a52a2a;
  --accent-light: #301010;
  --accent-dark: #d25a5a;

  --gradient-primary: transparent;
  --gradient-secondary: #121211;
  --gradient-hero: #0a0a09;
  --gradient-glass: transparent;

  --glass-bg: transparent;
  --glass-border: transparent;
  --glass-shadow: none;

  --success: #438f61;
  --success-light: #162a1f;
  --warning: #d69e38;
  --warning-light: #2b1f09;
  --danger: #d25a5a;
  --danger-light: #301010;

  --border-color: #2a2a2a;
  --border-focus: #a52a2a;

  --shadow-sm: none;
  --shadow-md: none;
  --shadow-lg: none;
}

/* --- RESET & ACCESSIBILITY --- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  transition:
    background-color var(--transition-normal),
    color var(--transition-normal);
}

/* Focus Ring for Keyboard Navigation */
*:focus-visible {
  outline: 2px solid var(--border-focus);
  outline-offset: 2px;
}

/* Reset Links and Buttons */
a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

button {
  font-family: inherit;
  background: none;
  border: none;
  cursor: pointer;
  outline: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* --- TYPOGRAPHY --- */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.text-serif {
  font-family: var(--font-serif);
}

.text-mono {
  font-family: var(--font-mono);
}

/* --- GLOBAL LAYOUT CONTAINERS --- */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.container-narrow {
  width: 100%;
  max-width: var(--container-narrow);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* --- REUSABLE BUTTONS --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.625rem 1.25rem;
  font-size: 0.95rem;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  gap: 0.5rem;
}

.btn-primary {
  background-color: var(--accent);
  color: #fff;
}
.btn-primary:hover {
  background-color: var(--accent-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
}
.btn-secondary:hover {
  background-color: var(--bg-secondary);
  border-color: var(--text-tertiary);
}

.btn-danger {
  background-color: var(--danger);
  color: #fff;
}
.btn-danger:hover {
  background-color: hsl(0, 75%, 45%);
}

.btn-sm {
  padding: 0.375rem 0.75rem;
  font-size: 0.85rem;
}

/* --- FORM CONTROLS --- */
.form-group {
  margin-bottom: 1.25rem;
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
}

.form-control {
  width: 100%;
  padding: 0.75rem 1rem;
  font-family: inherit;
  font-size: 0.95rem;
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  transition:
    border-color var(--transition-fast),
    box-shadow var(--transition-fast);
}

.form-control:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(var(--hue), 85%, 45%, 0.15);
}

/* --- BADGES & TAGS --- */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.5rem;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-primary {
  background-color: var(--accent-light);
  color: var(--accent);
}

/* --- CARDS --- */
.card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition:
    transform var(--transition-normal),
    box-shadow var(--transition-normal);
  overflow: hidden;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

/* --- GLASSMORPHISM EFFECTS --- */
.glass {
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

.glass-card {
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--glass-shadow);
  transition:
    transform var(--transition-normal),
    box-shadow var(--transition-normal);
}

.glass-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.15);
}

/* --- GRADIENT BACKGROUNDS --- */
.gradient-bg {
  background: var(--gradient-primary);
}

.gradient-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.gradient-border {
  position: relative;
  background: var(--bg-surface);
  border-radius: var(--radius-md);
}

.gradient-border::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-md);
  padding: 2px;
  background: var(--gradient-primary);
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  mask-composite: exclude;
  pointer-events: none;
}

/* --- TOAST NOTIFICATIONS --- */
#toast-container {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  z-index: 10000;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  pointer-events: none;
}

.toast {
  pointer-events: auto;
  min-width: 280px;
  max-width: 380px;
  background-color: var(--bg-surface);
  color: var(--text-primary);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  box-shadow: var(--shadow-xl);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  transform: translateY(1.5rem);
  opacity: 0;
  transition:
    transform var(--transition-normal),
    opacity var(--transition-normal);
}

.toast.show {
  transform: translateY(0);
  opacity: 1;
}

.toast-success {
  border-left-color: var(--success);
}
.toast-warning {
  border-left-color: var(--warning);
}
.toast-error {
  border-left-color: var(--danger);
}

.toast-close {
  color: var(--text-tertiary);
  cursor: pointer;
  font-size: 1.15rem;
  transition: color var(--transition-fast);
}
.toast-close:hover {
  color: var(--text-secondary);
}

/* --- SKELETON LOADING SKELETONS --- */
.skeleton {
  background: linear-gradient(
    90deg,
    var(--bg-secondary) 25%,
    var(--bg-tertiary) 37%,
    var(--bg-secondary) 63%
  );
  background-size: 400% 100%;
  animation: skeleton-loading 1.4s ease infinite;
  border-radius: var(--radius-sm);
}

@keyframes skeleton-loading {
  0% {
    background-position: 100% 50%;
  }
  105% {
    background-position: 0% 50%;
  }
}

.skeleton-text {
  height: 12px;
  margin-bottom: 8px;
}

.skeleton-text-sm {
  height: 10px;
  margin-bottom: 6px;
  width: 80%;
}

.skeleton-title {
  height: 24px;
  margin-bottom: 16px;
  width: 60%;
}

.skeleton-image {
  height: 200px;
  width: 100%;
}

.skeleton-avatar {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-round);
}

.skeleton-card {
  padding: 1.5rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.skeleton-button {
  height: 40px;
  width: 120px;
  border-radius: var(--radius-sm);
}

/* Pulse animation for loading states */
@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

.loading-pulse {
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* Shimmer effect */
.shimmer {
  position: relative;
  overflow: hidden;
}

.shimmer::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 255, 255, 0.2) 50%,
    transparent 100%
  );
  animation: shimmer 2s infinite;
}

@keyframes shimmer {
  0% {
    transform: translateX(-100%);
  }
  100% {
    transform: translateX(100%);
  }
}

/* --- BACK TO TOP WHIP --- */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  left: 2rem;
  background-color: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  width: 44px;
  height: 44px;
  border-radius: var(--radius-round);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all var(--transition-normal);
  z-index: 99;
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background-color: var(--bg-secondary);
  color: var(--accent);
}

/* --- READING PROGRESS BAR --- */
.progress-bar-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  z-index: 1001;
  background-color: transparent;
}

.progress-bar {
  height: 100%;
  width: 0%;
  background: var(--gradient-primary);
  transition: width 0.1s ease-out;
}

/* --- SCROLL ANIMATIONS --- */
.scroll-trigger {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.scroll-trigger.visible {
  opacity: 1;
  transform: translateY(0);
}

.scroll-trigger.from-left {
  transform: translateX(-50px);
}

.scroll-trigger.from-right {
  transform: translateX(50px);
}

.scroll-trigger.from-left.visible,
.scroll-trigger.from-right.visible {
  transform: translateX(0);
}

.scroll-trigger.scale-up {
  transform: scale(0.95);
}

.scroll-trigger.scale-up.visible {
  transform: scale(1);
}

/* Staggered animation delays */
.scroll-trigger:nth-child(1) { transition-delay: 0.1s; }
.scroll-trigger:nth-child(2) { transition-delay: 0.2s; }
.scroll-trigger:nth-child(3) { transition-delay: 0.3s; }
.scroll-trigger:nth-child(4) { transition-delay: 0.4s; }
.scroll-trigger:nth-child(5) { transition-delay: 0.5s; }